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81.
Habib M.R. Rashid M.H. Islam M.A. Majumder S. Islam K.M.S. Ahmed S. Alam M.S. Vargas-Bello-Pérez E. 《Tropical animal health and production》2018,50(4):889-895
Tropical Animal Health and Production - The objective of this study was to monitor the changes in growth, dry matter intake, and blood profiles (nutrition and reproductive hormones) of dairy... 相似文献
82.
Rahman M. Motiur Yasushi Furukawa Isao Kawata Mohammed Mahabubur Rahman Mahbubul Alam 《Journal of Forest Research》2006,11(2):89-97
Empirical information regarding the role of homestead forests in household economy is essential in understanding the importance
of these resources. Identification of the factors that affect homestead forest production and understanding forest owners'
attitudes toward key forest management issues have great significance in making appropriate policy responses to manage these
resources on a sustainable basis. In Bangladesh, homestead forests are claimed to play an important economic role in rural
livelihoods, but no reliable quantitative information exists. This study was undertaken to investigate the role of homestead
forests in the household economy, examine if forest production and income vary across landholding size classes, to explore
the relationships of homestead forest production with species richness, education level, and household size, and to assess
the attitude of homestead forest owners toward key forest management issues. Results show that homestead forests contribute
15.9% of the household income and generate 51.4 man-days of employment per household per year. Production of homestead forests
significantly varies across landholding size classes. It was observed that forest production depends significantly on species
richness of homestead forests and the education level of forest owners. However, no such relationship was found between forest
production and household size. The study revealed that farming families depend more on forest income than nonfarming families.
Attitudes of forest owners toward key forest management issues differ significantly across landholding size classes. For example,
although the majority of the forest owners prefer fruit species to timber species, the percentage of respondents decreased
as the landholding size class increased, while the opposite trend was observed for timber species. The findings of this study
suggest that diversification of forests and extension of education amongst forest owners would improve forest production.
Furthermore, forest policy should address the concerns of the forest owners in different landholding classes and focus on
their specific requirements to enhance sustainable forest management. 相似文献
83.
Carlton WK Gump B Fugelsang K Hasson AS 《Journal of agricultural and food chemistry》2007,55(14):5620-5625
An analytical method was developed to quantify levels of acetaldehyde in wine samples. The method utilizes headspace solid-phase microextraction with on-fiber derivatization using O-(pentafluorobenzyl)hydroxylamine and quantification by gas chromatography with flame ionization detection. The technique showed good sensitivity and reproducibility in samples of Chardonnay, Petite Sirah, and Merlot wines containing acetaldehyde at levels below the sensory threshold (40-100 ppm). The method was used to monitor acetaldehyde concentrations during the micro-oxygenation of Merlot wine in a 141 L pilot-plant experiment and a 2400 L full-scale study. In both experiments, levels of acetaldehyde remained constant for several weeks before increasing at rates of the order of 1 ppm/day. Variations in the levels of acetaldehyde present are discussed within the context of the underlying chemical reactions. 相似文献
84.
Ten multiparous crossbred local Zebu cows were randomly divided into two nutritional groups (A and B) to determine the effect of urea-molasses-mineral block supplementation on body weight gain, milk production, and onset of ovarian cyclicity after calving. Both groups had farm rations daily, but the supplemented group (B) was provided with an additional diet daily of 250 g urea-molasses-mineral block. The cows in group A required 80-120 days (98.0 +/- 6.7 days) until peak milk progesterone concentrations and 60-80 days (72.0 +/- 3.8 days) were required for group B (p<0.05). Group B needed a shorter period for expression of standing estrus (91-101 days; mean 96.2 +/- 2.3 days) than group A [130-153 (141.6 +/- 4.6) days; p<0.01]. For groups A and B, body weight gain was 8.4 +/- 3.4 kg and 18.4 +/- 3.2 kg, respectively (p<0.01). The average milk production of groups A and B were 3.3 +/- 1.0 and 4.8 +/- 1.6 L/day, respectively (p>0.05). There was linear improvement in milk yield from Day 60 postpartum up to Day 90 of lactation in group B (supplemented). However, in group A, milk production decreased starting on Day 40 after parturition. 相似文献
85.
Khalijah Awang Xe-Min Loong Kok Hoong Leong Unang Supratman Marc Litaudon Mat Ropi Mukhtar Khalit Mohamad 《Fitoterapia》2012
A study on the leaves of Aglaia exima led to the isolation of one new and seven known compounds: six triterpenoids and two steroids. Their structures were elucidated and analyzed mainly by using spectroscopic methods; 1D and 2D NMR, mass spectrometry, UV spectrometry and X-ray. All the triterpenoids and steroids were measured in vitro for their cytotoxic activities against eight cancer cell lines; lung (A549), prostate (DU-145), skin (SK-MEL-5), pancreatic (BxPC-3), liver (Hep G2), colon (HT-29), breast (MCF-7) and (MDA-MB-231). The new cycloartane triterpenoid, 24(E)-cycloart-24-ene-26-ol-3-one 1, showed potent cytotoxic activity against colon (HT-29) cancer cell line (IC50 11.5 μM). 相似文献
86.
The 1H- and 13C-NMR spectral data of ovatodiolide (1), a diterpenoid from Anisomeles indica, and its anti-HIV activity are reported. 相似文献
87.
Sharoni Shafir Arnon Dag Alon Bilu Mohamad Abu-Toamy Yigal Elad 《European journal of plant pathology / European Foundation for Plant Pathology》2006,116(2):119-128
Botrytis cinerea, which causes grey mould, is a major pathogen of many crops. On strawberry, isolates of Trichoderma spp. can effectively control B. cinerea, but frequent application is necessary. Bees can be used to disseminate biological control agents to the target crop. We tested the ability of honey bees to disseminate Trichoderma harzianum T39 to control B. cinerea in strawberry in the field during the winter in Israel over two consecutive seasons. We used the recently developed ‘Triwaks’ dispenser for loading the bees with the T. harzianum inoculum. During both years, grey mould developed in late January in untreated control plots; at low to medium disease levels it was partially controlled by fungicide treatment, and was best controlled in bee-visited plots. At high disease levels neither chemical nor biological control was effective. To assess the spatial distribution of inoculum by bees, we sampled flowers up to 200 m from the hives and found effective levels of T. harzianum even at 200 m. The approach used in this study provides an effective control of grey mould in strawberry in conditions of low to medium grey mould incidence. 相似文献
88.
Alam Sundaram 《Pest management science》1987,20(2):105-118
The viscosity, surface tension and volatility of a range of ultra-low-volume (ULV) spray diluents and pesticide formulations were measured at 5°C and 20°C. For u.l.v. application of 1.0 to 1.5 litre ha?1 through conventional boom and nozzle systems or rotary (Micronair) atomisers, it is concluded that the spray medium should have a viscosity of ?30 mPa s at 20°C. The surface tension values covered only a narrow range and showed little temperature dependence. There was no clear optimum and all surface tensions within the range measured would appear to be acceptable for ULV applications. The volatility factor, 1/(A.T1/2), where A represents the percentage of non-volatile material in the spray mixture and T1/2, the half-life (minutes) of evaporation, should be <40 times; 10?5. 相似文献
89.
Bacteria of the family Chlamydiaceae are obligate intracellular pathogens of human and animals. Chlamydophila pecorum is associated with different pathological conditions in ruminants, swine and koala. To characterize a coding tandem repeat (CTR) identified at the 3' end of incA gene of C. pecorum, 51 strains of different chlamydial species were examined. The CTR were observed in 18 of 18 tested C. pecorum isolates including symptomatic and asymptomatic animals from diverse geographical origins. The CTR were also found in two strains of C. abortus respectively isolated from faeces from a healthy ewe and from a goat belonging to asymptomatic herds, but were absent in C. abortus strains isolated from clinical disease specimens, and in tested strains of C. psittaci, C. caviae, C. felis and C. trachomatis. The number of CTR repeats is variable and encode several motifs that are rich in alanine and proline. The CTR-derived variable structure of incA, which encode the Chlamydiaceae-specific type III secreted inclusion membrane protein, IncA, may be involved in the adaptation of C. pecorum to its environment by allowing it to persist in the host cell. 相似文献
90.
Jahangir A Watanabe Y Chinen O Yamazaki S Sakai K Okamura M Nakamura M Takehara K 《Avian diseases》2008,52(1):49-53
Among winter migratory waterfowl, Northern pintails (Anas acuta), in one of the largest flocks in Tohoku district, northeast Japan, were surveyed for influenza A viruses at five wintering sites in three prefectures, viz., Aomori, Akita, and Miyagi. A total of 38 influenza A viruses were isolated from 2066 fecal samples collected during November 2006 through March 2007. The overall isolation rate was 1.84%. Eleven different subtypes were isolated, including nine H5N2, seven H6N8, seven H10N1, four H4N6, three H6N1, three H11N9, and one each of H1N1, H6N2, H6N5, H10N9, H11N1. Only the H4N6 subtype was detected during two successive months, November and December, from Lake Ogawara of Aomori prefecture. One wintering site, Lake Izunuma of Miyagi prefecture, was negative for virus isolation throughout the study period. During the sampling period, the highest virus isolation rate was in December (4.90%) followed by November (2.18%), January (0.91%), and February (0.30%). Virus isolation was negative for samples collected in March 2007. These results suggest that influenza viruses are introduced by Northern pintail when they migrate into Japan, but the viruses are not maintained in the flocks, most likely because the birds are not breeding during the winter. We believe that this relatively large data set creates a strong foundation for future studies of avian influenza virus (AIV) prevalence, evolution, and ecology in wintering sites, along with the role of Northern pintails in the spread of AIV during their migration from northern Russia and Asia to Japan. 相似文献